Those with a penchant for outdoor adventure, such as hikers, mountain climbers and whitewater enthusiasts, often find themselves in locations where standard communication services are lacking. Although cellular telephone towers seemingly are popping up everywhere one looks, in fact there are still many locations in the world were cellular telephone service is not available. In these out of the way areas, cellular phones are at times of no use if an emergency situation arises.
One option available to signal for help when in remote locations is the personal locator beacon (PLB). These devices generally comprise an RF transmitter that transmits an intermittent pulse which may be received by orbiting satellites. These PLB devices do not provide for any sort of two-way communication with search and rescue personnel. Thus, an injured mountain climber who activates a PLB in an emergency situation has no way of knowing whether the PLB signal has been received, or if help has been dispatched.
It is well known that the rate of survival of those lost or injured in the wilderness increases significantly if they know that their request for help has been received and that help is on the way.
What is needed, therefore, is an emergency signaling device that provides two-way communication between the person in an emergency situation and the emergency response personnel, even when the emergency has occurred in a remote location where no standard wireless communication services are available.